At this time, we do not have a feature that previews your ad in the Quora ecosystem on demand.
It is possible to visit specific pages, or webpages, associated with your Quora Ads campaign to trigger your targeting. For example, if you are targeting the "Finance" topic you can visit www.quora.com/topic/Finance.
However, please note that a variety of factors go into determining whether you will see your own ad on Quora at any given time. This includes your bid and bids of other advertisers, whether and how often you've seen your ad previously as well as your user activity on Quora.